Amplifiers are commonly used in various electronic devices to provide signal amplification. Different types of amplifiers are available for different uses. For example, a wireless communication device such as a cellular phone may include a transmitter and a receiver for bi-directional communication. The transmitter may utilize a driver amplifier (DA) and a power amplifier (PA), the receiver may utilize a low noise amplifier (LNA), and the transmitter and receiver may utilize variable gain amplifiers (VGAs).
To reduce cost and improve integration, metal oxide semiconductor field effect transistors (MOSFETs) are often used in radio frequency (RF) circuits in wireless devices and other applications. In particular, MOSFETs are often used in driver amplifiers for wireless devices.
Today's driver amplifiers for wireless devices require high quality linearity performance while at the same time requiring very strong reliability. Unfortunately, transistors, such as MOSFETs, used in present driver amplifiers for wireless devices, often provide non-linear performance and inadequate reliability. There is therefore a need in the art for an amplifier with both high quality linearity and reliability.